Leptin levels recover normally in healthy older adults after acute diet-induced weight loss.
OBJECTIVE
Involuntary weight loss affects 20% of community dwelling older adults. The underlying mechanism for this disorder is unknown. Objective is to determine if failure of older persons to regain weight is associated with elevated pro-inflammatory cytokine and leptin levels.


METHODS
Prospective diet intervention study.


METHODS
University of Washington Medical Center from 2001-2005.


METHODS
Twenty-one younger (18-35 years old) and nineteen older (>or= 70 years old) men and women.


METHODS
Each subject was placed for two weeks on a weight-maintaining diet, followed in sequence by 2 weeks of 30% caloric restriction, then 4 weeks of ad libitum food intake.


METHODS
Plasma leptin levels, fasting serum pro-inflammatory cytokine levels, and peripheral blood mononuclear cell cytokine levels were measured.


RESULTS
Leptin levels in the two cohorts decreased after caloric restriction and increased after ad-libitum food consumption resumed. Plasma TNF alpha levels were higher in older subjects compared to younger adults. However, there was no association between changes in TNF alpha levels and changes in AUC leptin.


CONCLUSIONS
Leptin levels in healthy older individuals responded appropriately in a compensatory manner to changes in body weight. These data do not support a cytokine dependent elevation in leptin levels as being responsible for the failure of older adults to regain weight.
Yukawa
M
M
Harborview Medical Center, Division of Gerontology and Geriatric Medicine, 325 9th Ave Box 359755, Seattle, WA 98104, USA. myukawa@u.washington.edu
Phelan
E A
EA
Callahan
H S
HS
Spiekerman
C F
CF
Abrass
I B
IB
Weigle
D S
DS
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000097:blood* / Q000276:immunology / Q000502:physiology; D019540:Area Under Curve; D016207:Cytokines / Q000097:blood; D004038:Diet, Reducing; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D009765:Obesity / Q000097:blood* / Q000178:diet therapy*; D015431:Weight Loss / Q000502:physiology*; D055815:Young Adult
D016207:Cytokines; D020738:Leptin